1. Field
The present invention provides a method of preparing a negative active material for a rechargeable lithium battery, and a negative active material and a rechargeable lithium battery prepared therefrom.
2. Description of the Related Art
At present, a crystalline graphite material is being used as a negative active material for a rechargeable lithium battery. The crystalline graphite is classified into artificial graphite and natural graphite. Since the artificial graphite is obtained by heat-carbonizing a common carbon precursor at a high temperature of greater than or equal to about 2800° C. under an inert atmosphere through impurity removal and graphitization, the natural graphite has been increasingly used in recent times.
However, a flake-shaped natural graphite particle as a negative active material has a problem of deteriorating uniformity due to anisotropic characteristics of its shape when slurry is coated to manufacture an electrode, and also sharply deteriorates battery characteristics since the particle is arranged along with a current collector by compression and pressure. Accordingly, spherically-shaped natural graphite obtained by assembling flake-shaped graphite into a spherical shape is commercially available. However, the spherically-shaped natural graphite requires improved high-rate charge and discharge and cycle-life characteristics.